CH 5
To retrieve data from multiple tables in a query you can use the ____ operator with a subquery.
IN
If you precede the subquery by the ____ operator, the condition is true only if it satisfies all values produced by the subquery.
all
If you precede the subquery by the ____ operator, the condition is true only if it satisfies any value (one or more) produced by the subquery.
any
The product of two tables is formally called the ____ Product.
cartesian
When a subquery involves a table listed in the outer query, the subquery is called a(n) ____ subquery.
correlated
The ____ of two tables is the set of all rows that are in the first table but that are not in the second table.
difference
For an SQL implementation to truly support the union operation, it must remove ____ rows automatically.
duplicate
You can precede a subquery with the ____ operator to create a condition that is true if one or more rows are obtained when the subquery is executed.
exists
For two tables to be union compatible, the columns of the two tables must be identical.
false
In a nested query, the outer query is evaluated first.
false
In small databases, there is a significant time difference between different query approaches.
false
The product operation is commonly used.
false
There are three types of inner joins.
false
There is only one approach to joining tables.
false
To produce the same results as the INTERSECT operator, use the BETWEEN operator and a subquery.
false
To relate two tables, in the FROM clause list all columns involved in the query.
false
When joining tables, it is always necessary to qualify a column name.
false
When the innermost subquery is evaluated, a permanent table is produced.
false
You can join three tables together but not four tables.
false
You must use a comma or a period to separate a table name from its alias.
false
In a(n) ____ join, all rows from both tables are included regardless of whether they match rows from the other table.
full outer
Which of the following joins compares the tables in the FROM clause and lists only those rows that satisfy the condition in the WHERE clause?
inner
Oracle and SQL Server support the ____ operator but Microsoft Access does not.
intersect
The ____ of two tables is a table containing all rows that are in both tables.
intersect
In a ____, all rows from the table on the left (the table listed first in the query) will be included regardless of whether they match rows from the table on the right (the table listed second in the query).
left outer join
To qualify a column name, precede the name of the column with the name of the table, followed by a(n) ____.
period
In a ____, all rows from the table on the right will be included regardless of whether they match rows from the table on the left.
right outer join
A(n) ____ clause can include statistics calculated for only the groups or columns whose values are identical for each row in a group.
select
You create an alias by typing the name of the table, pressing the ____, and then typing the name of the alias.
spacebar
In a full outer join, all rows from both tables will be included regardless of whether they match rows from the other table.
true
It is easy to create a product inadvertently by omitting the WHERE clause when you are attempting to join tables.
true
It is permissible to qualify all column names in a query.
true
Occasionally, a self-join might involve the primary key of a table.
true
One reason for using an alias is simplicity.
true
One reason for using an alias is when you are joining a table to itself.
true
Oracle supports the INTERSECT operator.
true
SQL Server does not support the MINUS operator.
true
Table A has 10 rows and table B has 7 rows. The product of Table A and Table B would have 70 rows.
true
To ensure that query results are listed in a desired order, use the ORDER BY clause.
true
To produce the same results as the MINUS operator, use NOT, the IN operator and a subquery.
true
When using a DBMS without an optimizer, the formulation of a query can make a difference in the speed with which the query is executed.
true
You can join tables by using a condition in the WHERE clause.
true
You can perform special operations, such as self-joins, within SQL.
true
You can use the ALL and ANY operators with subqueries to produce a single column of numbers.
true
You can use the EXISTS operator to retrieve data from more than one table.
true
You can use the IN operator to retrieve data from multiple tables.
true
You must join tables by finding rows in the two tables that have identical values in matching columns.
true
The ____ of two tables is a table containing every row that is in either the first table, the second table, or both tables.
union
Two tables are ____ compatible if they have the same number of columns and if their corresponding columns have identical data types and lengths.
union
You can join tables by using a condition in the ____ clause.
where